Feeding the World

Sect. 1 Objectives Identify the major causes of malnutrition. Compare the environmental costs of producing different types of food. Explain how food distribution problems and drought can lead to famine. Explain the importance of the green revolution.

Nutrition What is good nutrition/a balanced diet? – 4 food groups Dairy - calcium Protein Bread – carbohydrates Fruits and veggies - vitamins – My Food Pyramid mypyramid.gov What are Calories? How many should you have a day?

Malnutrition – when someone does not eat enough calories or different foods to fulfill the bodies needs. Corn or Rice diets = protein malnutrition – Effects physical and mental development – Majority of foods produced in the world are carbohydrates

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Ecology of Food Food efficiency energy + resources = FOOD Cow = 1,000,000 calories per acre Corn = 2,000,000 calories per acre Potatoes = 8,500,000 calories per acre Which has the highest yield? What would you plant to feed a large population?

World Food Problems The world currently produces enough grain to feed 10 billion people. – People eat too much – People want meat – Poverty More money = more technology/equipment = more food

Impact on Environment Livestock vs. Grains – What are livestock fed? – Where is that grown? – What is the yield?

The Green Revolution New varieties of grains yield more on the same land – Lowered the price But!! – They use more fertilizer and water – Some farmers don’t have the money to upgrade

Agriculture Crops and Soil

Sect. 2 Objectives Distinguish between traditional and modern agricultural techniques. Describe fertile soil. Describe the need for soil conservation. Explain the benefits and environmental impacts of pesticide use. Explain what is involved in integrated pest management. Explain how genetic engineering is used in agriculture.

Traditional Plowing – pushed by farmer or pulled by livestock Fertilization – Manure and plant waste Irrigation – Water flowing through a ditch Pest Control – ?? Weeding – Pulled by hand

Modern Plowing and harvesting – machines Fertilization – Synthetic chemicals Irrigation – Overhead sprinklers and drip systems Pest Control – Synthetic chemicals

Soil Fertile – can support the growth of healthy plants – Fertile topsoil = organisms, rocks, water, air, organic matter (dead and decomposing organisms) Soil is rocks broken down into tiny pieces – Takes thousands of years

How do organisms help make fertile soil?

Topsoil Erosion

Land Degradation - when land is damaged so it cannot support the local ecosystem Desertification – making land more desert like Ex: Sahel desert – fallow period disappearing

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Soil Conservation Ways to conserve: – Terracing – Contour plowing – Drip irrigation – No-till farming

Compost - partly decomposed organic matter Adds nutrients to the soil Manure Food waste Yard waste

Pest Control Worldwide – insects destroy about 33% of food crops Wild plants vs. food crops – natural defenses

Pesticides – chemicals used to kill insects, weeds, and other crop pests Chemicals do the job very well – But at what cost?? Resistance – the ability of an organism to survive exposure to a particular pesticide Pollution - DDT

Biological Pest Control – the use of living organisms to control pests Pathogens Genetically modified foods – bred to have defenses against pests – Chemical defenses – chemicals that repel pests – Physical defenses – tougher skin Natural plant chemicals as a pesticide Introduction of nonnative species – Can be very harmful Pheromones – confuse insects

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Pest Control Timeline Biological – natural proceedures Cultivation control – vacuuming insects Insecticides New Insesticide

The Day it Rained Cats Malaria – carried by mosquitoes DDT Dead wasps Roofs fell in – too many caterpillars Tin roof Dead cats Rats Plague Flying Cats

Genetic Engineering - when genetic material is modified to produce a better product Selective breeding – early GE GE today – taking good genes from one organism and inserting them into another Creates Genetically Modified (GM) Foods We still do not know that full remifications of GE our food. – Salmon genes in tomotoes

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Sustainable Agriculture - farming that conserves natural resources and helps keep the land productive indefinatly Low energy input Low water Low pesticides Low fertilizers Pest resistance crops

Animals and Agriculture

Sect. 3 Objectives Explain how overharvesting affects the supply of aquatic organisms used for food. Describe the current role of aquaculture in providing seafood. Describe the importance of livestock in providing food and other products.

Animals Domesticated – animals that are bred and managed for human use – Cows, horse, pig, fish etc. Overharvesting – taking more organisms from a population than the population can replace – No-fishing zones – Examples?

Aquaculture - raising aquatic organisms for human use and consumption 20% of the animal protein eaten around the world Fish Farms Oyster farms Ranch – raised till they are a certain age the released – Ex: salmon Produces pollution b/c of excess waste

Livestock Provide food, leather, wool, eggs, fertilizer, etc. Ruminants – cud-chewing animals that have 3 or 4 chambered stomachs – Ex: cow, sheep, goats – Can digest cellulose from plants that humans can’t